var a = ['a','b','c','d']
var b = ['a','b','c','d','e','e']

console.log(a.find( x => x==='d'))
console.log(a.findIndex( x => x==='d'))
console.log(b.findIndex( x => x==='e'))

var c = 'Foo '.repeat(5)
console.log(c)

console.log('hello'.startsWith('llo',2))
console.log('hello'.endsWith('hell',4))
console.log('hello'.includes('ell'))
console.log('hello'.includes('ell',1))
console.log('hello'.includes('ell',2))
